I think it's a bit too fast to conclude that Houben's not conscious--brain scans could indeed have provided good evidence that he is. But what would be worse than having "locked-in syndrome"? Having somebody else purporting to speak for you with ideomotor-driven Facilitated Communication, while you were helpless to do anything about it.

I'd like to see some double-blind tests of Houben, where he's asked questions about events that occur when the facilitator isn't present, as well as fMRI results during the process of facilitation (since there are brain activation differences between active and passive activities, which have been used to study such things as the perception of involuntariness during hypnosis--it shows features of both active and passive movement). I'd also like to see further opinion on Laureys methodology and diagnosis--it seems he has significant self-interest in promoting this case.

The spectacle is so incredible that even Steven Laureys, the neurologist who discovered Mr Houben’s potential, had doubts about its authenticity. He decided to put it to the test.

“I showed him objects when I was alone with him in the room and then, later, with his aide, he was able to give the right answers,” Professor Laureys said. “It is true.”

and

Mr Houben’s “rebirth” took many painstaking months. “We asked him to try and blink but he couldn’t; we asked him to move his cheek but he couldn’t; we asked him to move his hand and he couldn’t,” Mrs Wouters said.

“Eventually, someone noticed that when we talked to him he moved his toe so we started to try and communicate using his toe to press a button.”

It was a breakthrough but much more was to come when a fellow speech therapist discovered that it was possible to discern minuscule movements in his right forefinger.

Mrs Wouters, 42, was assigned to Mr Houben and they began to learn the communication technique that he is now using to write a book about his life and thoughts. “I thought it was a miracle — it actually worked,” she said.

The method involves taking Mr Houben by the elbow and the right hand while he is seated at a specially adapted computer and feeling for minute twitches in his forefinger as his hand is guided over the letters of the alphabet. Mrs Wouters said that she could feel him recoil slightly if the letter was wrong. After three years of practice the words now come tumbling out, she said.

This still seems hard to rationalize with the video footage of the typing occurring while he's apparently asleep. Mrs. Wouters admits the possibility of "tak[ing] over" for him:

“The tension increases and I feel he wants to go so I move his hand along the screen and if it is a mistake he pulls back. As a facilitator, you have to be very careful that you do not take over. You have to follow him.”

UPDATE (November 25, 2009): Neurologist Steven Novella has weighed in. He suggests that Houben may have recovered some brain function and be conscious, but that the facilitated communication in the videos is positively bogus.

I've noted on the discussion page of Dr. Steven Laureys' Wikipedia entry that the paper in BMC Neurology that purportedly included Houben as a subject claims that all patients in the study were in a minimally conscious state (MCS) but had been misdiagnosed as being in a persistent vegetative state (PVS). The criteria of the study say that those that recovered and emerged from MCS were excluded, which seems at odds with claims that Houben's brain function is "almost normal." A story in Nature443, 132-133 (14 September 2006) by Mike Hopkin, "'Vegetative' patient shows signs of conscious thought," which quotes Laureys, is about a different patient, in a persistent vegetative state, who showed some signs minimal consciousness. When asked to visualize herself playing tennis, for example, she showed corresponding brain activity. But, as that article noted, that kind of neural response isn't necessarily a sign of consciousness:

But what that 'awareness' means is still up for debate. For example, Paul Matthews, a clinical neuroscientist at Imperial College London, argues that the brain imaging technique used cannot evaluate conscious thought; fMRI lights up regions of brain activity by identifying hotspots of oxygen consumption by neurons. "It helps us identify regions associated with a task, but not which regions are necessary or sufficient for performing that task," he says.

Matthews argues that the patient's brain could have been responding automatically to the word 'tennis', rather than consciously imagining a game. He also points out that in many vegetative cases, the patient's motor system seems to be undamaged, so he questions why, if they are conscious, they do not respond physically. "They are simply not behaving as if they are conscious," he says.

Owens counters that an automatic response would be transient, lasting for perhaps a few seconds before fading. He says his patient's responses lasted for up to 30 seconds, until he asked her to stop. He believes this demonstrates strong motivation.

He does admit, however, that it is impossible to say whether the patient is fully conscious. Although in theory it might be possible to ask simple 'yes/no' questions using the technique, he says: "We just don't know what she's capable of. We can't get inside her head and see what the quality of her experience is like."

But then again, as someone who's been reading a lot of literature on automaticity and voluntary action lately, it appears to me likely that a lot of our normal actions are automatic, the product of unconsciously driven motor programs of routine behavior.

Laureys is quoted in the article with a note of skepticism:

"Family members should not think that any patient in a vegetative state is necessarily conscious and can play tennis," says co-author Steven Laureys of the University of Liège, Belgium."It's an illustration of how the evaluation of consciousness, which is a subjective and personal thing, is very tricky, especially with someone who cannot communicate."

The article goes on to note that this woman, who is possibly somewhere between PVS and MCS, "seems to have been much less severely injured than the permanently vegetative Terri Schiavo" (as the report from her Guardian Ad Litem (PDF) made clear).

3 comments:

My local paper had a breathless AP version of this story on its front page this morning and like Randi I was disgusted with the completely credulous reporting. You're right that we don't know enough to say one way or the other what's going on, but I would have hoped the AP would have higher standards than to just uncritically promote this story without even giving the fact that he's reportedly communicating with the help of a facilitator.